v3.3.0

• Support EventTarget emitters in events.once from Node.js 12.11.0.

  Now you can use the events.once function with objects that implement the EventTarget interface. This interface is used widely in
  the DOM and other web APIs.

  var events = require('events');
  var assert = require('assert');
  
  async function connect() {
    var ws = new WebSocket('wss://example.com');
    await events.once(ws, 'open');
    assert(ws.readyState === WebSocket.OPEN);
  }
  
  async function onClick() {
    await events.once(document.body, 'click');
    alert('you clicked the page!');
  }